Caption: Scanning electron micrograph (SEM) of Odorous house ant (Tapinoma sessile). Odorous house ants are common household pests that usually feed on sweets, but also on grease and protein. These small (3 millimetre long) dark brown ants derive their name from the disagreeable odour, similar to that of rotten coconuts, that is given off when worker ants are crushed. Found throughout the U. S, these ants usually nest outdoors and prefer sweet honeydew produced by insects such as aphids and mealy bugs. Under wet or hot conditions they nest indoors in walls or under floors spaces. Odorous house ants travel in trails and prefer sweets although they eat almost any household food. Magnification: x12 when shortest axis printed at 25 millimetres.